1029 science project ideas, from class 1 to college.

What it shows

Air rushing backwards out of the balloon pushes the car forwards. This is Newton’s third law: every action has an equal and opposite reaction.

You will need

• A balloon and a drinking straw
• A plastic bottle or stiff cardboard for the body
• Four bottle caps for wheels
• Two wooden skewers or straws for axles
• Tape and glue

Take it further: Try a bigger balloon or a wider straw, and measure how far the car travels each time.

What it shows

Magnets attract things made of iron and most kinds of steel, but not paper, plastic, wood, aluminium or copper.

You will need

• A small magnet tied to a string and a stick
• Paper fish with a paper clip on each
• Objects to test: coins, foil, keys, erasers
• A tray or box as the pond

Safety: Keep small magnets away from young children who might swallow them.

Take it further: Guess which of 15 objects are magnetic before testing, then count how many you got right.

What it shows

Sound is a vibration. Your voice makes the cup vibrate, the tight string carries the vibration, and the other cup turns it back into sound.

You will need

• Two paper cups
• 3 to 10 metres of string
• Two toothpicks or matchsticks
• A pencil to make the holes

Take it further: Does it still work when the string is slack or touching something? Try thread, wool and fishing line.

What it shows

Electricity flows only round a complete loop. The switch opens and closes the loop, turning the bulb off and on.

You will need

• Two AA cells in a holder
• A torch bulb in a holder, or an LED
• Insulated wires
• A switch, or one made from a drawing pin and a paper clip
• A cardboard base

Safety: Use cells only, never a mains socket. Do not join the two ends of a cell directly with a wire: it gets hot.

Take it further: Put different objects in the gap to find out which are conductors and which are insulators.

What it shows

Whether something floats depends on its density and its shape. A ball of clay sinks, but the same clay shaped into a boat floats, because it pushes aside more water.

You will need

• A tub of water
• Objects such as a coin, a cork, a key, a leaf and a plastic spoon
• Modelling clay
• Small coins or marbles to load the boat

Take it further: Which boat shape carries the most coins before it sinks?

What it shows

Air pushes on everything around us. When the glass is turned over, the air pressure pushing up on the card is enough to hold the water in.

You will need

• A glass filled to the brim with water
• A smooth postcard or stiff card

Safety: Do it over a sink or a bucket.

What it shows

Air from the balloon forms a thin cushion under the CD. The cushion cuts friction with the table, so the hovercraft glides.

You will need

• An old CD
• A pop-up bottle cap
• A balloon
• Glue

What it shows

Pressure applied to a liquid in a closed system is passed on equally in every direction (Pascal’s law), so pushing one syringe moves its partner and lifts the arm.

You will need

• 4 to 8 plastic syringes without needles
• Plastic tubing to fit
• Water, coloured so it is easy to see
• Cardboard or ice-cream sticks
• Nuts, bolts or split pins for joints
• A glue gun

Safety: An adult should handle the glue gun.

Take it further: Fill one pair with air instead of water. Why does that joint feel springy?

What it shows

An electric current in a coil of wire makes a magnetic field. Wound round an iron nail, the coil becomes a magnet you can switch off, and more turns of wire make it stronger.

You will need

• A large iron nail
• Enamelled copper wire
• A 1.5 V cell in a holder
• Paper clips
• Sandpaper to clean the wire ends

Safety: The wire and cell get warm: disconnect between tests. Use cells only, never the mains.

Take it further: Count how many paper clips it lifts with 20, 40 and 60 turns, and plot a graph.

What it shows

A coil carrying current in a magnetic field feels a force and turns. Scraping the insulation off only half of one end switches the current on and off at the right moments, so the coil keeps spinning.

You will need

• Enamelled copper wire
• A D-size or AA cell
• Two large safety pins
• A small strong magnet
• A rubber band
• Sandpaper

Safety: The wire gets hot if left connected: unhook it between runs.

What it shows

Light reflects from a plane mirror at the same angle at which it arrives. Two mirrors at 45 degrees send the light down the tube, so you can see over a wall.

You will need

• Two juice cartons or a long cardboard box
• Two small mirrors
• Tape and scissors

Safety: Cover the mirror edges with tape.

What it shows

A small DC motor works as a generator when its shaft is turned: the spinning blades turn motion energy into electrical energy that lights the LED.

You will need

• A small DC motor
• Blades cut from a plastic bottle or card
• An LED
• Wires
• A stand of pipe or wood

Take it further: An LED lights only one way round, so if it stays dark swap its leads or spin faster. Then compare three blade shapes.

What it shows

Rubbing a balloon moves electric charge onto it. A charged object attracts light things, and in the electroscope the two foil leaves get the same charge and push apart.

You will need

• A glass jar with a card lid
• A metal paper clip or thick wire
• Two small strips of aluminium foil
• A balloon or a plastic comb

Take it further: Static works best on dry days. Try it on a humid day and compare.

What it shows

Light travels in straight lines, so rays from the top of an object pass through the pinhole and land at the bottom of the screen. The image is upside down.

You will need

• A box or a tube
• Butter paper or tracing paper
• Aluminium foil and a pin
• Black paper and tape

Safety: Never point it at the Sun.

What it shows

Winding the rubber band stores elastic potential energy, which turns into motion (kinetic) energy as it unwinds and turns the axle.

You will need

• Cardboard or a bottle for the body
• Old CDs or bottle caps for wheels
• Skewers or straws for axles
• Rubber bands
• Tape

What it shows

A small fan blows air out of the back of the bottle, lowering the pressure inside, so outside air rushes in through the nozzle carrying dust and paper bits with it.

You will need

• A plastic bottle
• A small DC motor with a fan cut from a bottle cap or tin
• A battery pack and a switch
• A mesh or cloth filter
• Wires and glue

Safety: Keep fingers away from the spinning fan.

What it shows

When a coil turns in a magnetic field, the changing magnetic field through it induces a current (Faraday’s law). The current reverses every half turn, which is alternating current.

You will need

• Enamelled copper wire for the coil
• Strong magnets
• A wooden or plastic frame and an axle
• Slip rings and brushes
• An LED or a galvanometer

What it shows

The eye lens focuses light on the retina. In short sight the image forms in front of the retina and a concave lens corrects it; in long sight it forms behind the retina and a convex lens corrects it.

You will need

• A round-bottomed flask of water, or a ball model of the eye
• Convex and concave lenses
• A screen as the retina
• A torch

What it shows

Light inside the water meets the surface at a large angle and is totally internally reflected, so it follows the curved stream. Optical fibres carry internet signals the same way.

You will need

• A clear plastic bottle with a hole near the bottom
• Water
• A low-power laser pointer or a bright torch
• A dark room and a basin

Safety: Never shine a laser into anyone’s eyes. Use a low-power pointer, with an adult.

What it shows

Water stored high up has potential energy. As it falls it turns a turbine, and a generator on the turbine’s shaft turns that motion into electricity.

You will need

• A raised bottle or tank as the dam
• A pipe
• A turbine made from plastic spoons or a bottle cap
• A small DC motor as the generator
• An LED and wires

What it shows

Pumped-in air pushes the water out of the nozzle downwards, and the rocket is pushed upwards (Newton’s third law). A little water gives far more thrust than an empty bottle.

You will need

• A fizzy-drink PET bottle
• Card fins and a nose cone
• A cork or a launcher with a valve
• A bicycle pump
• Water

Safety: Launch outdoors in an open space with an adult. Wear eye protection, never stand over the rocket, and do not over-pump.

What it shows

Four diodes arranged as a bridge send current through the load in the same direction on both halves of the AC cycle, turning AC into pulsating DC. A capacitor smooths the output.

You will need

• Four 1N4007 diodes
• An enclosed, ready-made low-voltage step-down transformer or a low-voltage AC supply
• An electrolytic capacitor and a load resistor or LED
• A breadboard and a multimeter

Safety: Never wire or touch the mains side yourself: use an enclosed transformer or a low-voltage AC supply from your teacher.

What it shows

Two diodes and a resistor make AND and OR gates, and a transistor makes a NOT gate. Switches give the inputs and an LED shows the output, matching each gate’s truth table.

You will need

• Diodes, resistors and a BC547 transistor
• Two switches and LEDs
• A 5 V supply or battery pack
• A breadboard

What it shows

Alternating current in the primary coil makes a changing magnetic field in the iron core, which induces a voltage in the secondary coil (mutual induction). In an ideal transformer the voltages are in the same ratio as the numbers of turns.

You will need

• A laminated iron core or a soft-iron ring
• Enamelled copper wire for two coils with different numbers of turns
• A low-voltage AC supply in the school lab
• An AC voltmeter or a small bulb

Safety: Never connect a home-made transformer to the mains. Use only a low-voltage AC supply, with your teacher.